<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
</head>
<body>
<button id="btn">按钮</button>
<div id="box"></div>
</body>
<script type="text/javascript">
    $("#btn").click(function(){
        $.post(
            'post.php',
            {'data':"person"},
            function (data) {
                alert(data);
                $("#box").html(data);
            }
        );
    })
</script>
</html>